Various framing systems have been devised to reduce the cost and simplify the installation of certain structures. In the case of wall framing systems, the prior art discloses an upper channeled track and a lower channeled track which are secured to a ceiling and a floor respectively. Bridging the distance between the two tracks is a plurality of vertically extensible studs which may be adjusted in length to accommodate the dimensions of a room in which the frame will be installed. In such systems, the vertically extensible studs are most often composed of a thin gauge metal and, like the upper and lower channeled tracks, are provided with an elongated channel therein. Mounted within the elongated channels of the extensible studs are vertical extension mechanisms which typically provide for telescopic extension of a vertical extension member of the stud. Once the vertically extensible studs are fully extended such that the upper and lower ends of the studs are in contact with the upper and lower tracks respectively, they are attached to the upper track and decorative wall covering such as drywall panels or wood panels can be affixed to the wall frame.
Although the majority of known wall framing systems are generally configured as discussed above, various locking means have been developed for maintaining the extension members in the desired extended position. U.S. Pat. No. 3,492,766 discloses one such system in which the extension members are each provided with cutout tabs which may be manually bent back into contact with slots provided in the studs such that the extension members are prevented from being retracted into the studs. Although simple in design, these cutout tab systems have several drawbacks. Firstly, since locking is only accomplished with manual bending back of the cutout tabs, these systems are labor intensive and do not have the advantage of being self-locking. Furthermore, due to the difficulty in bending back the cutout tab while simultaneously maintaining the extension member in the fully extended position, the extension member is likely to retract slightly into the stud during the locking procedure. Moreover, in that the thin gauge cutout tab is the only mechanism preventing retraction of the extension member, these systems do not appear capable of functioning as load bearing structures.
In another known system disclosed in U.S. Pat. No. 3,897,668, the extension members are spring-loaded so as to be self-adjusting to the height of the ceiling. Although this feature simplifies the installation process, such a system, like the cutout tab systems, do not appear to be usable in load bearing applications. Accordingly, the wall frame cannot be pressure fit in place to ensure wall rigidity.
In U.S. Pat. No. 5,433,046, a plurality of bearings and brackets are used to provide for the extension and locking of an extension portion of a frame. The complexity of this system and the associated expense of its fabrication, however, present a significant drawback to the typical unskilled installer.
It is to be noted that none of the above described systems disclose a lateral extension mechanism with which the width of the frame may be adjusted.
Accordingly, it can be seen that it would be desirable to provide an adjustable frame system which is both easy to install and inexpensive to produce. Moreover, it would be desirable to provide such a frame which further is self-locking and may be used in load bearing situations. Further, it would be desirable to provide such a frame which also includes lateral extension mechanisms with which the width of the frame can be adjusted.